[Nuriho Launch] Korean Researchers Searching Museum Achieve Success After 10 Years (Comprehensive)

The History of South Korea's Space Launch Vehicle Development: 10 Decisive Moments

[Image source=Yonhap News]

[Asia Economy Reporter Kim Bong-su] Launching a space launch vehicle is not an easy task. Hundreds of thousands of components must work organically to generate hundreds of tons of force to overcome Earth's gravitational pull. Previously, only six countries worldwide possessed the technology to actually launch satellites into space. Since it is directly linked to national security, technology transfer is refused even if other countries offer large sums of money. The technical staff from Korea Aerospace Research Institute (KARI) and Hanwha Aerospace, who started from scratch, overcame difficulties by sketching while looking at old rocket engines displayed in old books or at the National Air and Space Museum in Washington DC, USA.

Korea's space launch vehicle development began on June 4, 1993, with the launch of the first-stage scientific rocket KSR-I. In 1997, the improved KSR-II was launched, and in 2002, the first domestically produced liquid-propellant rocket KSR-III was successfully launched. The institutional foundation for space launch vehicle development was also established with the confirmation of the mid- to long-term basic space development plan in May 1996 and the establishment of the first basic space development promotion plan in 2007. The Naro Space Center, completed in 2009, was also important. Only 13 countries worldwide have space centers. Korea was freed from the predicament of having no place to manufacture, test, and launch rockets and having to rely on overseas facilities. The successful launch of Naroho in January 2013, after great effort, was a historic moment as the first space launch vehicle launched from Korean soil. Although the first-stage engine was imported from Russia, KARI accumulated all the technology necessary for space launch vehicle development, including the design and manufacture of a 30-ton class liquid engine.

Finally, in March 2010, the development of Nuriho began. Despite the large technological gap and limited development personnel, and being ridiculed as "impossible," the development of a three-stage space launch vehicle capable of launching a 1.5-ton class practical satellite into low Earth orbit was decided. The biggest technical challenge was the development of the rocket's heart?the engine. At one point, combustion instability issues surfaced, leading to more than ten design changes. After a grueling march, a turbopump-type liquid engine was developed that supplies fuel at a rate of 1 ton per second, producing tremendous thrust. The development of the propellant tank was also a continuous challenge. Special welding technology was developed to manufacture tanks up to 10 meters long and 3.5 meters in diameter using 2mm-thick special aluminum alloy steel plates.

Finally, in November 2018, the test launch of a test vehicle equipped with a single 75-ton engine was successfully conducted. This marked the moment Korea became the seventh country in the world to develop a medium-sized liquid engine. The clustering technology applied to the first stage was also highly challenging but was overcome. It was not easy to cluster four 75-ton liquid engines together and coordinate them organically to produce thrust in a consistent direction. The first launch of Nuriho was initially scheduled for May but was postponed to October due to delays in clustering technology development. In January, the clustered first-stage combustion test succeeded, and the final combustion test was completed in March, enabling the October launch. Subsequently, the three-stage assembly of Nuriho was completed, and on June 1, it was showcased as a complete vehicle for the first time. Then, on the 21st of this month, it finally left a new milestone in the history of Korean space development.

This content was produced with the assistance of AI translation services.